Trying to fit 2 MPG

[Clive S]

You could of maybe mentioned that in your previous post

I don't see why as I gave the correct info to do the job.

OK
a) connect 8-12 V to the bob centre two terminals near the blue relay
b) connect 5 V or the USB to the bob
c) connect 5 V to the mpg + & - and A & B to input pins via a 1k resistor pins 10 and 11 (or any of the inputs)

Job done , You will have to set the pins up and high/low in Mach3. I used Linuxcnc
you might have to change the sense of the pins in Mach3 I used Linuxcnc

Edit : If you need to use the bob to drive the VFD (0-10v) you need to power the BOB with at least 12V
but if you don't need that the MPG will work with just 5V connected to the same pins at a) above